AURIFEROUS ORES.

Thames Star, Volume XII, Issue 4014, 9 November 1881, Page 2

AURIFEROUS ORES.

The following extract from the London Times may be of interest to many of our > readers:—"A number of gentlemen assembled yesterday at the Works of the Foreign and . Colonial Tunnelling and Prospecting Company, in Guildford street, York Boad, Lambeth, to inspect various kinds of gold mining appliances, and to witness a demonstration of a new chemical system of treating complex.auriferous ores. There were present the Bight Hod. Lyon Flayfair, C.8., M.P., chairman of the company; Colonel fiolton, Colonel ' Beaumont, the Agent • General for Queensland, and others interested in gold mining and metallurgical operations. The chemical process is that of Messrs Molloy and Warren, and ita ' object is the extraction of gold and silver from ores of a refractory character, such as telurides pyrites, arsenical pyrites, &c, which can only be partially treated by the ordinary methods of extraction.' In the new system the ore is first crashed and roasted, and these processes were shown in operation by means of the Beaumont steam stamp which works direct, and is similar in action to a steam hammer, and an ordinary reverberating furnace. The ore is then placed in a stone tank, and there subjected to a nitro hydrochloric solvent. . The liquid solution is drawn of!' into a settling tank, and from thence into a precipitating tank, where the gold is precipitated as a fine powder. This powder is then placed in an ordinary crucible and melted down into gold bars. Should there be any silver present, it is obtained by washing the residual ore, precipitating and melting down the pro* duct as in the case of gold. The chief point is that about 90 per cent, of the acid is recovered after use, otherwise the practice would prove too expensive, as has been the case previously, when tried in practice. It is claimed that by this process the whole of the gold and silver is extracted from the ore, however refractory ' it may be. This is, in fact, done ,by ordinary analysis by the wet process, which, however, involves the loss of the acid. By means of the process discovered by Messrs MoHoy aud Warreu, the same acid is used over and over again, with only a fractional loss, as was demonstrated at the experiments. The plant and machinery employed are of a simple character, and appear to be subject only to slow deterioration.